Field of the Invention
The present invention relates to a laminated body and an electronic device. The present application claims a priority based on Japanese Patent Application No. 2015-218773 filed on Nov. 6, 2015. The entire content of Japanese Patent Application No. 2015-218773 is incorporated herein by reference.
Description of the Background Art
Graphene is a substance in which carbon atoms form sp2 hybrid orbitals and are bonded two-dimensionally. Due to such a bonding state of carbon, graphene is characterized as having a very high carrier mobility. Hence, by using a graphene film as a channel of an electronic device such as a transistor, it is expected to attain high speed of the electronic device, for example.
By producing a laminated body including the graphene film and by forming an electrode or the like on the laminated body, it is possible to manufacture an electronic device employing the graphene film as a conductive portion (for example, channel). The laminated body including the graphene film can be manufactured, for example, in the following manner: a graphene thin film detached from graphite is adhered to a supporting substrate; or a graphene thin film grown by CVD (Chemical Vapor Deposition) is adhered to a supporting substrate.
In order to secure acceptable production efficiency in mass-producing electronic devices, a supporting substrate having a large diameter (for example, having a diameter of not less than 2 inches) is preferably employed in the laminated body. In the laminated body produced in the procedure including the adhesion of the graphene film as described above, a large region with no graphene film is included in a surface of the supporting substrate. In such a case, automation is obstructed in a process of manufacturing the electronic devices, such as alignment for electrode formation. As a result, it becomes difficult to mass-produce electronic devices each employing the laminated body described above, disadvantageously.
To address this, the following method has been proposed: a substrate composed of SiC (silicon carbide) is heated to separate Si atoms in order to convert a surface layer portion of the substrate into graphene, thereby obtaining a laminated body in which a graphene film is formed on a substrate (for example, see Japanese Patent Laying-Open No. 2015-48258). This reduces the region with no graphene film on the main surface of the substrate. As a result, mass production of electronic devices using the laminated body is facilitated.